Noob with a BR question that may help other Noobs

[smogthemog]

Hi.

Name is Jim and am in the UK.
Just getting into all this laser diode malarkey moving over from 'the old Gas lasers' that I dabbled with a few years back.
I have to date a Wicked GXII (not here yet but it's on it way (got it cheap from a good source so I know it's not a duffer, and yes I have read all the blurb on how crap the company is ) A 100mw green pointer (EBay - firststepahead) that nicely lights matches and pops red balloons , several red modules and an old red gas thingy that I no longer have a PSU for.

I have soon to arrive on my doorstep a good PS3 carriage and a bag of 10x Aixiz 12mm body's (all off good old EBay )

I have spent many many hours trolling through the plethora of info on this and a few other sites and just cannot come to a clean decision as to what driver cct to use with it, what safe voltage to use with said driver cct and diode and how to eventually measure the driver current when connected to my new spangling BR diode, that will give me best results.
I am the sort of guy that once explained to me in layman's terms - I get it ! and can then go on from there to make things happen for me :
I suffer from ADD so reading lots of pages of info is very hard for me to do so I am asking if someone could please just cap this one off for me so I know what to order, and what to basically NOT do when I start building in order to make this project work first time and not fry the diode.
I have looked at Bluefusion's cct's and at DDL's cct's in particular but am a bit boozwaggled as to which one/type will be best.

Any help will be GREATLY appreciated and may well help others in their search for a quick and sure answer
Thanks

Jim (Lincs, UK)

 

[rog8811]

Re: Noob with a BR question that may help other No

Hi Jim and welcome.  Blue rays require around 4.5 volts @ less than 40ma to lase.
I have no experience of Bluefusions circuit but I have successfuly used DDL's LM317 and also Gazoo's 7805. The LM circuit is used for constant current and the 7805 as constant voltage. Are you looking to build a pointer or a labby style?

For pointer I use 7805 as it requires less overhead voltage and can be run from 7.2v supplied from 2 RCR123 battteries. The LM needs a 3v overhead so your best bet is a 9v PP3 supply.

setting up both circuits is straightforward enough, this thread tells you how:-

http://www.laserpointerforums.com/forums/YaBB.pl?num=1197651171

For the blue ray replace the string of Diodes with a 100 ohm resistor, to keep the maths easy keep the 1 ohm in as well then mw = ma output to the LD.....turn the ma up until the LD lases then add a max of 10ma more.

I am sure others will chime in with more tips.

Regards rog8811 (Berkshire )

 

[Vcent]

Re: Noob with a BR question that may help other No

Bluefusions seems to not be finished yet,so i would stick with ddl's first,a general rule of thumb is 6v for reds & 9v for blu-rays,although with ddls circuit ive heard you can drive it w/ up to 37v...!With proper heat sinking!i would still use 9v though,since the rest wont make any difference except heat...

 

[smogthemog]

Re: Noob with a BR question that may help other No

Thanks for your answers people, it's SO much clearer now.

When measuring the current values you talk of, is it measuring these values with a MM set to mA (obviously) in series with the battery input or is it in series with the LD/Driver board?


I am looking to install it all into an aluminium torch housing so I may well go for the 7805 voltage reg cct and use the 2x RCR123 batt's. That's not to say I won't try the 317 route but I won't get the PP3 in to the housing.

 

[rog8811]

Re: Noob with a BR question that may help other No

When measuring the current values you talk of, is it measuring these values with a MM set to mA (obviously) in series with the battery input or is it in series with the LD/Driver board?

If you look at the drawing, post 2 of the thread I linked to, the MM is across the 1 ohm resistor set to millivolts, which converts directly to milliamps i.e. 40mv is equal to 4ma.

Regards rog8811